One of Chomsky’s most revolutionary findings was that the corpus (language performance) was a poor tool for linguistic study. Instead, he argued that competence, our internalized knowledge of a language, is much more significant to understanding language and its mental mechanisms than performance which he viewed as external, and flawed, evidence that does not accurately reveal competence. A corpus is an external collection of utterances or performance data which he saw as a poor tool for modeling linguistic competence. If performance is a poor measure of competence then, Chomsky argued, it is impossible

The inherent language faculty, then, acts as an interface level of linguistic competence. Chomsky developed this theory to explain how children from different cultural backgrounds are able to speak their native language at basically the same age of development regardless of differences in intelligence and experience and despite a lack of training. This faculty draws the line between language and cognition. The difference is that the language faculty is language specific at the attained state but the cognitive functions that are encompasses in language knowledge are not, “The underlying structure is language specific (in the inventories of syntactic relations, morphological values and lexical units, and, possibly, also in some issues of categorization of the content), cognitive structuring itself (as studies by intensional logic, by situational semantics, or by formal semantic theories) does not depend on the patterns of individual languages” (Sgall 1). Those who are opposed to Chomsky’s argument believe that all we have to measure competence is the behavioral dispositions of the speakers.

Nonetheless, Sapir’s linguistic theories were quite significant during the 1930s, 1940s, and even the 1950s. Chomsky argued the universal principles and their parameters allowed the individual a measure of freedom independent of the environment and particular language of their culture. Sapir, on the other hand, did not believe there was any significant measure of freedom in the individual associated with language. As a matter of fact, Sapir’s view held that language is the dominant phenomenon that shapes the individual and their relation to the world and their understanding of it. As he wrote in 1929 “Human beings do not live in the objective world alone, nor alone in the world of social activity as ordinarily understood, but are very much at the mercy of the particul